1. Faculty of Mathematics, Voronezh State University, Voronezh, Russia
2. Faculty of Physics and Mathematics, Voronezh State Pedagogical University, Voronezh, Russia
3. Department of Healthcare Administration and Medical Informatics, Center for Big Data Analytics and Intelligent Healthcare, and Research Center of Nonlinear Analysis and Optimization, Kaohsiung Medical University, Kaohsiung, Taiwan
4. Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
5. Center for Fundamental Science, and Research Center for Nonlinear Analysis and Optimization, Kaohsiung Medical University, Kaohsiung, Taiwan