I’m currently a Software Engineer at Duolingo working on speech tasks in the Duolingo learning app and test center. Before that, I worked at M*Modal as a Research Scientist on improving speech recognition for medical transcription. I received my PhD and MS degrees from the Language Technologies Institute of Carnegie Mellon University under the supervision of Prof. Alex Rudnicky. I also received a MS and a BS degree from the University of Science and Technology of China.

CV [pdf]

Research

1. •Deep learning (DNN) in speech recognition
   

2. •Automatic Speech Assessment
   

3. •Voice Activity Detection (VAD)
   

4. •Out-of-vocabulary (OOV) word learning
   

5. •Discriminative acoustic modeling
   

6. •Speaker adaptive training (SAT)
   

7. •Unsupervised / semi-supervised lexicon learning
   

8. •Statistical parametric speech synthesis
   

Selected PublicationS

1. •PhD Dissertation: Learning out-of-vocabulary words in automatic speech recognition, Carnegie Mellon University. [document] [presentation]
   

2. •Building a vocabulary self-learning speech recognition system, Interspeech-2014. [pdf]
   

3. •Learning better lexical properties for recurrent OOV words, ASRU-2013. [pdf]
   

4. •Using web text to improve keyword spotting in speech, ASRU-2013. [pdf]
   

5. •Finding recurrent OOV words, Interspeech-2013. [pdf]
   

6. •OOV word detection using hybrid models with mixed types of fragments, Interspeech-2012. [pdf]
   

7. •System combination for out-of-vocabulary word detection, ICASSP-2012. [pdf]
   

8. •OOV detection and recovery using hybrid models with different fragments, Interspeech-2011. [pdf]
   

9. •The effect of lattice pruning on MMIE training, ICASSP-2010. [pdf]
   

10. •Implementing and improving MMIE training in SphinxTrain, CMU Sphinx Workshop 2010. [pdf]
    

Courses

1. •10-701 Machine Learning
   

2. •11-711 Algorithm for NLP
   

3. •11-721 Grammars and Lexicons
   

4. •11-733 Multilingual Speech to Speech Translation
   

5. •11-741 Information Retrieval
   

6. •11-751 Speech Recognition and Understanding
   

7. •11-752 Speech II
   

8. •11-754 Dialog System
   

9. •11-756 Design and Implementation of ASR Systems
   

10. •11-761 Language and Statistics
    

11. •11-791 Software Engineering
    

Interests

Football, Soccer, Movie, Ski, Skate