1. School of Electronic Engineering and Computer Science, Queen Mary University of London, 4617 London, London, United Kingdom of Great Britain and Northern Ireland, E1 4NS (e-mail: h.phan@qmul.ac.uk)
2. Department of Engineering Science, University of Oxford, 6396 Oxford, Oxfordshire, United Kingdom of Great Britain and Northern Ireland, (e-mail: yibing.chen@seh.ox.ac.uk)
3. Nuffield Division of Anaesthetics, University of Oxford, 6396 Oxford, Oxfordshire, United Kingdom of Great Britain and Northern Ireland, (e-mail: minh.tran@chch.ox.ac.uk)
4. Institute for Signal Processing, University of Lbeck, Lbeck, Schleswig-Holstein, Germany, (e-mail: ph.koch@uni-luebeck.de)
5. Institute for Signal Processing, University of Lbeck, Lbeck, Schleswig-Holstein, Germany, (e-mail: alfred.mertins@uni-luebeck.de)
6. Department of Electrical Engineering, KU Leuven, 26657 Leuven, Flanders, Belgium, (e-mail: maarten.devos@kuleuven.be)