1. Department of Mathematics; National Institute of Technology Rourkela; Odisha India
2. College of Mathematics and Statistics; Chongqing University; Chongqing P.R. China
3. Department of Mathematics; KIIT University; Bhubaneswar, Odisha India
4. Institute of Reliability Engineering; University of Electronic Science and Technology of China; Chengdu, Sichuan P.R. China