Acknowledgements
I would like to thank all the authors who have contributed towards this special issue. I am also extremely grateful to all the reviewers who have accepted the difficult task for selecting papers. The expertise they have done was very efficient so as to ensure a high quality of the issue and fit to the good reputation of the journal. Finally, my sincere thanks go to Prof. Andrew Adamatzky as Editor in Chief of IJPEDS for helping me to have this special issue.