Research

My doctoral research (January 2002 – December 2005) focused on analyzing time series and signals emanating from complex systems like the economy, the human body, and physical phenomena like solar flares and earthquakes. In my thesis, I proposed that scaling is a universal phenomenon of time series characterizing the behavior of complex systems and that wavelet analysis is a universal tool with which we can study complex systems across various domains. I developed, tested, and validated a wavelet-based interdisciplinary decision support system as part of my doctoral work. My PhD advisor was Professor Steve Schneider and my thesis examiners were Professor John S Shawe-Taylor (external) and Professor Peter Tino (external) while Professor Josef Kittler acted as the Chair.

During my postdoctoral training at the Ottawa Hospital (June 2006 – January 2009), I worked in the Dynamical Analysis Laboratory (DAL) – a hospital-based laboratory led by Dr. Andrew J. E. Seely (MD, PhD, FRCSC). My research in the DAL focused on exploring the diagnostic, prognostic, and therapeutic value of monitoring the dynamics of physiologic variables such as heart rate variability (HRV) and respiration rate variability (RRV), employing a plurality of mathematical and computational techniques. In Dr. Seely’s lab, I worked on the development of algorithms for computation of metrics such as wavelets, detrended fluctuation analysis (DFA), sample entropy (sampEn), multiscale entropy (MSE), Fourier transform (FFT), power law analysis, and time irreversibility for characterizing physiologic variability. Of particular note was the THRIVE (Temperature and Heart Rate Investigation along with Variability Evaluation) investigation whereby we observed statistically significant drops in multi-parameter HRV 24-48 h prior to the clinical diagnosis of systemic infection in bone marrow transplant (BMT) patients. Results of the THRIVE study were published in the journal PLoS One and it received FRONT PAGE MEDIA COVERAGE in the Ottawa Citizen.

As a research associate in the School of Information Technology and Engineering (SITE), University of Ottawa (January 2009 – Present), I am working on the development of algorithms for robust blood pressure monitoring in conjunction with exploring analysis paradigms for extracting physiologic information from oscillometric blood pressure wave data.

© Saif Ahmad

Last Modified: May 23, 2011