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Ortigueira, M, Tenreiro-Machado JA, da Costa JSá.  2005.  Which Differintegration?, July IEE Proceedings Vision, Image & Signal Processing. 152:846–850., Number 6: IET AbstractWebsite
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Batista, AG, English MJ.  1998.  "Ventricular Late Potential Analysis with Musical and Harmonic Wavelets. Medical Engineering and Physics. 20:773-779. Abstract
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Antunes, R, Coito F, Duarte-Ramos H.  2010.  Using Human Dynamics to Improve Operator Performance. Emerging Trends in Technological Innovation. :393–400.: Springer Abstract

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Pereira, P, Fino MH, Coito FV.  2009.  Using discrete-variable optimization for CMOS spiral inductor design. Microelectronics (ICM), 2009 International Conference on. :324–327.: IEEE Abstract

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Coito, F, Gomes L, Costa A, Palma L.  2008.  The Use of Remote Laboratory Activities within the Learning Process. Abstract

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Coito, F, Palma LB.  2011.  Unfalsification based Fault Tolerant Controller. Emerging Technologies & Factory Automation (ETFA), 2011 IEEE 16th Conference on. :1–4.: IEEE Abstract

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Ortigueira, M.  2005.  Two new integral formulae for the Beta function. International Journal of Applied Mathematics. 18:109–116., Number 1: International Association of Engineers AbstractWebsite
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Palma, LB, Coito FV.  2011.  Tuning PCA controllers based on manual control data. Emerging Technologies & Factory Automation (ETFA), 2011 IEEE 16th Conference on. :1–4.: IEEE Abstract

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Ktonas, PY, Golemati S, Xanthopoulos P, Sakkalis V, Ortigueira MD, Tsekou H, Zervakis M, Paparrigopoulos T, Bonakis A, Economou NT.  2009.  Time?frequency analysis methods to quantify the time-varying microstructure of sleep EEG spindles: Possibility for dementia biomarkers? Journal of Neuroscience Methods. 185:133–142., Number 1 AbstractWebsite

The time-varying microstructure of sleep EEG spindles may have clinical significance in dementia studies and can be quantified with a number of techniques. In this paper, real and simulated sleep spindles were regarded as AM?FM signals modeled by six parameters that define the instantaneous envelope (IE) and instantaneous frequency (IF) waveforms for a sleep spindle. These parameters were estimated using four different methods, namely the Hilbert transform (HT), complex demodulation (CD), matching pursuit (MP) and wavelet transform (WT). The average error in estimating these parameters was lowest for HT, higher but still less than 10% for CD and MP, and highest (greater than 10%) for WT. The signal distortion induced by the use of a given method was greatest in the case of HT and MP. These two techniques would necessitate the removal of about 0.4 s from the spindle data, which is an important limitation for the case of spindles with duration less than 1 s. Although the CD method may lead to a higher error than HT and MP, it requires a removal of only about 0.23 s of data. An application of this sleep spindle parameterization via the CD method is proposed, in search of efficient EEG-based biomarkers in dementia. Preliminary results indicate that the proposed parameterization may be promising, since it can quantify specific differences in IE and IF characteristics between sleep spindles from dementia subjects and those from aged controls.

  1995.  Time-Frequency and Wavelet Analysis of the Beat-by-Beat High Resolution Electrocardiogram. , Sussex: Sussex University Abstract

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Batista, AG, Rodrigues JM, Ortigueira MD.  2001.  Time-Frequency and Time-Scale Characterisation of the Beat-by-Beat High-Resolution Electrocardiogram. Sixth Portuguese Conference on Biomedical Engineering Proceedings. Abstract
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Pereira, P, Sallem A, Fakhfakh M, Fino MH, Coito F.  2012.  A Technology-Aware Optimization of RF Integrated Inductors. : Nova Science Publishers, Inc. Abstract

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Gomes, L, Coito F, Costa A, Palma LB.  2007.  Teaching, learning, and remote laboratories. Advances on remote laboratories and e-learning experiences. :189. Abstract

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Ortigueira, MD, Coito FJ.  2010.  System initial conditions vs derivative initial conditions. Computers & Mathematics with Applications. : Elsevier Ltd AbstractWebsite

The alternative system initial conditions versus the derivative initial conditions is focused in this paper. It is shown that Riemann?Liouville and Caputo initial conditions result from the corresponding derivative and not necessarily from the system at hand. To setup the correct system initialization, a formulation generalizing the integer order approach is presented. This is based on a generalization to the fractional environment of the well known jump formula. The obtained scheme is very general and does not depend on any transform. Besides, it can also be used in the time variant case. The Riemann?Liouville and Caputo initial conditions are interpreted in terms of this general framework and deduced equations where they are correct.

Ortigueira, MD, Coito FJ.  2010.  System initial conditions vs derivative initial conditions. Computers & Mathematics with Applications. 59:1782–1789., Number 5: Elsevier Abstract

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Costa, F, Coito F, Palma L.  2011.  Switched Unfalsified Multicontroller. Technological Innovation for Sustainability. :393–401.: Springer Abstract

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Coito, F, Lemos JM, Alves SS.  2005.  Stochastic Extremum Seeking in the Presence of Constraints. World Congress. 16:266–266., Number 1 Abstract

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Manuel Ortigueira, Machado, JA (Eds.).  2003.  Special Issue on Fractional signal Processing and applications. Signal Processing. 83:2285–2286., Number 11: Elsevier Abstract
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Batista, A, Pereira A.  2017.  Software Development for the Detection and Characterization of Rail Corrugation. Workshop on Railway track dynamics. : Faculty of Sciences and Technology/UNL
Coito, F, Almeida P, Palma LB.  2005.  SMCRVI-a Labview/Matlab based tool for remote monitoring and control. Emerging Technologies and Factory Automation, 2005. ETFA 2005. 10th IEEE Conference on. 2:6–pp.: IEEE Abstract

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Almeida, R, Ortigueira MD, Batista AG, Ktonas P.  2011.  Sleep Spindles: Decomposition, Parameterization and Applications. 19th IEEE Conference on Signal Processing and Communications Applications. Abstract
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Coito, F, Gomes L, Costa A.  2007.  Simulation, emulation and remote experiments. Proceedings of the Workshop on using VR in Education, Lisboa. :99–110.: Citeseer Abstract

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Palma, LB, Coito F, Neves-Silva R.  2004.  Sensor fault diagnosis based on neural observers and parameter estimation–application to the three-tank benchmark. VI Portuguese Conf. on Automatic Control, Faro. Indexed at ISI Web of Science. Abstract

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BRITO PALMA, L, VIEIRA COITO F, NEVES DA SILVA R.  2005.  Robust fault diagnosis approach using analytical and knowledge based techniques applied to a water tank system. : CRL Abstract

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Ortigueira, MD.  2007.  Riesz potentials as centred derivatives, September. 2nd Symposium on Fractional Derivatives and Their Applications. (J Sabatier, OP Agrawal, Machado, J.A.T., Eds.).:93–112.: Springer Abstract

Generalised fractional centred differences and derivatives are studied in this chapter. These generalise to real orders the existing ones valid for even and odd positive integer orders. For each one, suitable integral formulations are presented. The limit computation inside the integrals leads to generalisations of the Cauchy derivative. Their computations using a special path lead to the well known Riesz potentials. A study for coherence is done by applying the definitions to functions with Fourier transform. The existence of inverse Riesz potentials is also studied.