About the Authors

Bing Jiang

Affiliation National Engineering Laboratory of Speech and Language Information Processing, University of Science and Technology of China, Hefei, AnHui, China

Yan Song

songy@ustc.edu.cn

Affiliation National Engineering Laboratory of Speech and Language Information Processing, University of Science and Technology of China, Hefei, AnHui, China

Si Wei

Affiliation iFlytek Research, Anhui USTC iFlytek Co., Ltd., Hefei, AnHui, China

Jun-Hua Liu

Affiliation iFlytek Research, Anhui USTC iFlytek Co., Ltd., Hefei, AnHui, China

Ian Vince McLoughlin

Affiliation National Engineering Laboratory of Speech and Language Information Processing, University of Science and Technology of China, Hefei, AnHui, China

Li-Rong Dai

Affiliation National Engineering Laboratory of Speech and Language Information Processing, University of Science and Technology of China, Hefei, AnHui, China

Competing Interests

Authors Si Wei and Jun-Hua Liu are employed by Anhui USTC iFlytek Co, which is a private spin-off company from the authors' university. There are no patents, products in development or marketed products to declare. This does not alter the authors' adherence to all the PLOS ONE policies on sharing data and materials.

Author Contributions

Conceived and designed the experiments: BJ YS SW LRD. Performed the experiments: BJ JHL. Analyzed the data: BJ YS SW JHL IVM LRD. Wrote the paper: BJ YS IVM.