About the Authors

Xiguo Yuan

Affiliation School of Computer Science and Technology, Xidian University, Xi'an, P. R. China

Junying Zhang

Affiliation School of Computer Science and Technology, Xidian University, Xi'an, P. R. China

Shengli Zhang

Affiliation Department of Mathematics, Xidian University, Xi'an, P. R. China

Guoqiang Yu

Affiliation Bradley Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Arlington, Virginia, United States of America

Yue Wang

yuewang@vt.edu

Affiliation Bradley Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Arlington, Virginia, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: XY JZ YW. Performed the experiments: XY SZ. Analyzed the data: JZ SZ. Contributed reagents/materials/analysis tools: GY. Wrote the paper: XY JZ GY YW.