“…With the maturity of the development of fractional calculus theory, fractional differential equations have become research hot-spots for many mathematicians, and appear naturally in various fields such as fluid mechanics, fractals, environmental science, modeling and control theory, signal processing, bioengineering and biomedical science [1][2][3][4]. Due to the nonlocal properties of fractional derivatives, fractional differential equations can better describe complex processes and systems with genetic effects and memory.…”