1. College of Science, Hebei United University, Tangshan, China
2. College of Mechanical Engineering, Yanshan University, Qinhuangdao, China
3. School of Civil Engineering and Architecture, Chongqing Jiaotong University, Chongqing 400074, China
4. Faculty of Basic Sciences, Department of Mathematics, Ayatollah Amoli Branch, Islamic Azad University, Amol 4615143358, Iran
5. Department of Mathematics, University of Salerno, Via Ponte don Melillo, Fisciano, 84084 Salerno, Italy
6. Qinggong College, Hebei United University, Tangshan 063000, China