Acknowledgments. This research was supported by the NSF of China granted (71771030, 11301041, 71431008, 71371195, 71671018, 71471020, 71371065), Natural Science Foundation of Hunan Province(2015JJ3015), Scientific Research Fund of Hunan Provincial Education Department(16B005), and by Hunan International Economic and Project Management granted (17IEPM01).
This research was supported by the NSF of China granted (71771030, 11301041, 71431008, 71371195, 71671018, 71471020, 71371065), Natural Science Foundation of Hunan Province(2015JJ3015), Scientific Research Fund of Hunan Provincial Education Department(16B005), and by Hunan International Economic and Project Management granted (17IEPM01).