1School of Engineering and Built Environment, Glasgow Caledonian University, Glasgow G4 0BA, UK 2School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK 3School of Computer Science and Electronic Engineering, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK 4Department of Computer Science, Sun Yat-Sen University, Guangzhou 510060, China 5Department of Mechanical Engineering, University of Auckland, Private Bag 92019, Auckland, New Zealand