Francisco Sepulveda

Dr. Francisco Sepulveda

School of Computer Science and Electronic Engineering, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ, UK

Research Focus & Metrics

Academic Career Length

34Years (1993-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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24 March 2011 in Sensors
Verified
Journal Article
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MAMohammed Al-Mulla
Mohammed Al-Mulla
FSFrancisco Sepulveda
Francisco Sepulveda
MCMartin Colley
Martin Colley
Muscle fatigue is an established area of research and various types of muscle fatigue have been investigated in order to fully understand the condition. This paper gives an overview of the various non-invasive techniques available for use in automated fatigue detection, such as mechanomyography, electromyography, near-infrared spectroscopy and ultrasound for both isometric and non-isometric contractions. Various signal analysis methods are compared by illustrating their applicability in real-time settings. This paper will be of interest to researchers who wish to select the most appropriate methodology for research on muscle fatigue detection or prediction, or for the development of devices that can be used in, e.g., sports scenarios to improve performance or prevent injury. To date, research on localised muscle fatigue focuses mainly on the clinical side. There is very little research carried out on the implementation of detecting/predicting fatigue using an autonomous system, although recent research on automating the process of localised muscle fatigue detection/prediction shows promising results.


15 July 2009 in Journal of Neural Engineering
Verified
Journal Article
Closed access
MSM Salvaris
M Salvaris
FSFrancisco Sepulveda
Francisco Sepulveda
The best known P300 speller brain-computer interface (BCI) paradigm is the Farwell and Donchin paradigm. In this paper, various changes to the visual aspects of this protocol are explored as well as their effects on classification. Changes to the dimensions of the symbols, the distance between the symbols and the colours used were tested. The purpose of the present work was not to achieve the highest possible accuracy results, but to ascertain whether these simple modifications to the visual protocol will provide classification differences between them and what these differences will be. Eight subjects were used, with each subject carrying out a total of six different experiments. In each experiment, the user spelt a total of 39 characters. Two types of classifiers were trained and tested to determine whether the results were classifier dependant. These were a support vector machine (SVM) with a radial basis function (RBF) kernel and Fisher's linear discriminant (FLD). The single-trial classification results and multiple-trial classification results were recorded and compared. Although no visual protocol was the best for all subjects, the best performances, across both classifiers, were obtained with the white background (WB) visual protocol. The worst performance was obtained with the small symbol size (SSS) visual protocol.

12 February 2008 in IEEE Transactions on Neural Systems and Rehabilitation Engineering
Verified
Journal Article
Closed access
LCLuca Citi
Luca Citi
RPRiccardo Poli
Riccardo Poli
CCCaterina Cinel
Caterina Cinel
FSFrancisco Sepulveda
Francisco Sepulveda
In this paper we propose a brain-computer interface (BCI) mouse based on P300 waves in electroencephalogram (EEG) signals. The system is analogue in that at no point a binary decision is made as to whether or not a P300 was actually produced in response to the stimuli. Instead, the 2D motion of the pointer on the screen, using a novel BCI paradigm, is controlled by directly combining the amplitudes of the output produced by a filter in the presence of different stimuli. This filter and the features to be combined within it are optimised by an evolutionary algorithm.

1 February 1993 in Journal of Biomechanics
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Journal Article
Closed access
FSFrancisco Sepulveda
Francisco Sepulveda
DWDerek M. Wells
Derek M. Wells
CVChristopher Vaughan
Christopher Vaughan

17 April 2008 in Medical & Biological Engineering & Computing
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Journal Article
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AVAleksandra Vuckovic
Aleksandra Vuckovic
FSFrancisco Sepulveda
Francisco Sepulveda