Publications

Export 10 results:
Sort by: Author [ Title (Asc)] Type Year
A B C D E F G H [I] J K L M N O P Q R S T U V W X Y Z   [Show ALL]
I
Valério, D, Ortigueira MD, da Costa JSá.  2008.  Identifying a Transfer Function From a Frequency Response, April. Journal of Computational and Nonlinear Dynamics. 3:021207., Number 2 AbstractWebsite

In this paper, the classic Levy identification method is reviewed and reformulated using a complex representation. This new formulation addresses the well known bias of the classic method at low frequencies. The formulation is generic, coping with both integer order and fractional order transfer functions. A new algorithm based on a stacked matrix and its pseudoinverse is proposed to accommodate the data over a wide range of frequencies. Several simulation results are presented, together with a real system identification. This system is the Archimedes Wave Swing, a prototype of a device to convert the energy of sea waves into electricity.

Ortigueira, MD, Vale?rio D, da Costa J? S?.  2008.  Identifying a Transfer Function From a Frequency Response. Volume 5: 6th International Conference on Multibody Systems, Nonlinear Dynamics, and Control, Parts A, B, and C. :1405–1414. Abstract
n/a
Antunes, R, Coito F, Duarte-Ramos H.  2012.  Improving Operator Performance through the Use of a Multivariable Human-Machine Control Strategy. Technological Innovation for Value Creation. :95–104.: Springer Boston Abstract

n/a

Ortigueira, M, Coito F.  2008.  The Initial Conditions of Riemann-Liouville and Caputo Derivatives. 6th EUROMECH Conference ENOC 2008. Abstract
n/a
Ortigueira, M, Coito F.  2008.  The initial conditions of Riemann-Liouville and Caputo derivatives. Abstract

n/a

Ortigueira, M, Coito F.  2008.  Initial Conditions: What Are We Talking About? 3rd IFAC Workshop on Fractional Differentiation and its Applications. Abstract
n/a
Leal, A, Passão V, Calado E, Vieira JP, Cunha JP.  2006.  Interictal spike EEG source analysis in hypothalamic hamartoma epilepsy. Clinical Neurophysiology. (117):1595-1601.
Leal, A, Passão V, Calado E, Vieira JP, Cunha JP.  2002.  Interictal spike EEG source analysis in hypothalamic hamartoma epilepsy. Clinical Neurophysiology. (113):1961-1969.
Ortigueira, MD.  2008.  An introduction to the fractional continuous-time linear systems: the 21st century systems. IEEE Circuits and Systems Magazine. 8:19–26., Number 3: IEEE AbstractWebsite

A brief introduction to the fractional continuous-time linear systems is presented. It will be done without needing a deep study of the fractional derivatives. We will show that the computation of the impulse and step responses is very similar to the classic. The main difference lies in the substitution of the exponential by the Mittag-Leffler function. We will present also the main formulae defining the fractional derivatives.

Leal, A, Calado E.  2001.  Involuntary Rhythmic Leg Movements Time-Locked With the Respiratory Cycle. Pediatr Neurol . (25):405-408.