作者机构:[1]Science Department, Northeastern University Shenyang, Liaoning 110819, P. R. China, [2]Institute of Systems Science, Northeastern University Shenyang, Liaoning 110819, P. R. China
相关基金:This work was supported by National Science Foundation of China 61273008 and 61203001, Doctor Startup Fund of Liaoning Province (20131026), Fundamental Research Funds for the Central University (N140504005) and China Scholarship Council. The authors gratefully thank referees for their valuable suggestions.