[1] Univ Calcutta, Dept Pure Math, Kolkata 700073, W Bengal, India
[2] Jadavpur Univ, Sch Biosci & Engn, Kolkata 700032, W Bengal, India
[3] Comp & Informat Technol Coll, Comp Engn Dept, Lahore, Pakistan
[4] Haiphong Univ, Fac Informat Technol, Haiphong, Vietnam
[5] Bulgarian Acad Sci, Inst Syst Engn & Robot, Comp Syst Engn, BG-1040 Sofia, Bulgaria