The work described in this paper was supported by grants from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. 9042047, CityU 11208914) and National Natural Science Foundation of China(NSFC) (Grant No. 11402142 and Grant No. 51378448). The work was also supported by Hunan Provincial Natural Science Foundation of China (Project No. 14JJ2076), Aid Program for Teaching Reform Project of Changsha University of Science and Technology (Project No. JG1323), the Construct Program of the Key Discipline in Hunan Province and Aid Program for Science and the Technology Innovative Research Team in Higher Educational Institutions of Hunan Province, China.