1. Computer Engineering Department, College of Computer and Information Sciences, King Saud University, Riyadh, Saudi Arabia
2. Jülich Supercomputing Centre, Forschungszentrum Jülich, Germany and School of Engineering and Natural Sciences, University of Iceland, Reykjavik, Iceland
3. Faculty of Electrical Engineering and Computer Science, Technische Universität, Berlin, Germany
4. Department of Information Engineering and Computer Science, University of Trento, Trento, Italy