Browsing by Author "O'Toole J.M."
Now showing items 1-13 of 13
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Accurate and efficient implementation of the time–frequency matched filter
O'Toole, J.M.; Mesbah, M; Boashash, B ( Institution of Engineering and Technology , 2010 , Article)The discrete time-frequency matched filter should replicate the continuoustime-frequency matched filter, but the methods differ. To avoid aliasing, thediscrete method transforms the real-valued signal to the complex-valued ... -
Advanced implementation and realization of TFDs
Boashash, B.; Putland, G.R.; Stanković, L.J.; Bastiaans, M.J.; Van Leest, A.J.; Williams, W.J.; Aviyente, S.; Putland, G.R.; O'Toole, J.M.... more authors ... less authors ( Elsevier Inc. , 2016 , Book chapter)The design of efficient algorithms is the key to effective utilization of the properties of time-frequency distributions (TFDs) for real-life applications. This chapter presents the needed procedures, techniques, and ... -
Analysis of the time-varying cortical neural connectivity in the newborn EEG: A time-frequency approach
Omidvarnia, A; Mesbah, M; O'Toole, J.M.; Colditz, P; Boashash, B ( IEEE , 2011 , Conference Paper)Relationships between cortical neural recordings as a representation of functional connectivity between cortical brain regions were quantified using different time-frequency criteria. Among these, Partial Directed Coherence ... -
Fast and memory-efficient algorithms for computing quadratic time–frequency distributions
O'Toole, J.M.; Boashash, B ( Elsevier Inc , 2013 , Article)Algorithms for computing time–frequency distributions (TFDs) limit computation time by reducing numerical operations. But these fast algorithms do not reduce the memory load. This article presents four TFD algorithms to ... -
Improved Discrete Definition of Quadratic Time-Frequency Distributions
O'Toole, J.M.; Mesbah, M.; Boashash, B. ( IEEE , 2010 , Article)Computation of a time-frequency distribution (TFD) requires a discrete version of the continuous distribution. This discrete TFD (DTFD) should be free from aliasing and conserve all the important mathematical properties ... -
Instantaneous frequency based newborn EEG seizure characterisation
Mesbah M.; O'Toole J.M.; Colditz P.B.; Boashash B. (2012 , Article)The electroencephalogram (EEG), used to noninvasively monitor brain activity, remains the most reliable tool in the diagnosis of neonatal seizures. Due to their nonstationary and multi-component nature, newborn EEG seizures ... -
Kalman filter-based time-varying cortical connectivity analysis of newborn EEG
Omidvarnia, A.H.; Mesbah, M.; Khlif, M.S.; O'Toole, J.M.; Colditz, P.; Boashash, B.... more authors ... less authors ( IEEE , 2011 , Conference Paper)Multivariate Granger causality in the timefrequency domain as a representation of time-varying cortical connectivity in the brain has been investigated for the adult case. This is, however, not the case in newborns as ... -
A nonparametric feature for neonatal EEG seizure detection based on a representation of pseudo-periodicity
Stevenson, N.J.; O'Toole, J.M.; Rankine, L.J.; Boylan, G.B.; Boashash, B. ( Elsevier Ltd , 2011 , Article)Automated methods of neonatal EEG seizure detection attempt to highlight the evolving, stereotypical, pseudo-periodic, nature of EEG seizure while rejecting the nonstationary, modulated, coloured stochastic background in ... -
Orthogonalized partial directed coherence for functional connectivity analysis of newborn EEG
Omidvarnia A.H.; Azemi G.; Boashash B.; O'Toole J.M.; Colditz P.; Vanhatalo S.... more authors ... less authors (2012 , Conference Paper)The aim of this study is to develop a time-frequency method and test its applicability to investigating directional cortical connectivity in the newborn brain considering the effect of volume conduction. We modified ... -
Robust estimation of highly-varying nonlinear instantaneous frequency of monocomponent signals using a lower-order complex-time distribution
Omidvarnia, A.; Azemi, G.; O'Toole, J.M.; Boashash, B. ( Elsevier B.V. , 2013 , Article)This paper proposes an approach for robust estimation of highly-varying nonlinear instantaneous frequency (IF) in monocomponent nonstationary signals. The proposed method is based on a lower order complex-time distribution ... -
Time-frequency analysis of heart rate variability in neonatal piglets exposed to hypoxia
Dong S.; Mesbah M.; Lingwood B.E.; O'Toole J.M.; Boashash B. (2011 , Conference Paper)To determine whether the sympathetic nervous system plays any role in the inter-individual variation of cardiovascular response to hypoxia in newborns, neonatal heart rate variability (HRV) analysis was used to assess ... -
Time-frequency detection of slowly varying periodic signals with harmonics: Methods and performance evaluation
O'Toole J.M.; Boashash B. (2011 , Article)We consider the problem of detecting an unknown signal from an unknown noise type. We restrict the signal type to a class of slowly varying periodic signals with harmonic components, a class which includes real signals ... -
Time-frequency methodologies in neurosciences
Boashash, B.; Stevenson, N.J.; Rankine, L.J.; Stevenson, N.J.; Azemi, G.; Sejdić, E.; Aviyente, S.; Akan, A.; Mert, A.; Dong, S.; Omidvarnia, A.; Zarjam, P.; O'Toole, J.M.; Colditz, P.... more authors ... less authors ( Elsevier Inc. , 2016 , Book chapter)This chapter presents a number of time-frequency (t,f) techniques that can provide advanced solutions to several problems in neuro-sciences with focus on the monitoring of brain abnormalities using EEG and other physiological ...