1 Department of Computer Science and Information Engineering, Providence University, 200 Sec. 7, Taiwan Boulevard, Shalu District, Taichung City 43301, Taiwan.
2 Department of Computer Science and Communication Engineering, Providence University, 200 Sec. 7, Taiwan Boulevard, Shalu District, Taichung City 43301, Taiwan.
3 School of Computing and Mathematics, Computer Science Research Institute, University of Ulster, Jordanstown Campus, Shore Road, Newtownabbey, County Antrim BT37 0QB, UK.
4 Department of Computer Science and Information Engineering, Chang Gung University, No. 259, Wenhua 1st Road, Guishan District, Taoyuan City 33302, Taiwan.
5 Department of Computer Science, Arkansas State University, 2105 Aggie Road, Jonesboro, AR 72401, USA.