Chew Lim TAN
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Membership of Professional Bodies


  • 2008 - Professor, NUS
  • 1996 - 2008 Associate Professor, NUS
  • 1989 - 1995 Senior Lecturer, NUS
  • 1986 - 1988 Lecturer, NUS
  • 1982 - 1986 Senior Tutor, NUS
  • 1974 - 1982 Senior Scientific Officer, Dept of Scientific Services, Ministry of Health


Editorial Board Membership


  • Document Image Analysis
  • Text Mining
  • Natural Language Processing

Research Publications

  • Total Number of Publications: over 450
  • Total No. of Citations (according to Google Scholar): 8239
  • H-index: 47

27Research Grants

  • Total No. of Grants received as Principal Investigator: 25 (Total Amount: US$2.8 million)
  • Total No. of Grants received as Collaborator: 3 (Total Amount: US$1.8 million)

Research Awards

  • ANWRESH 2014: Competition on Word Recognition from Segmented Historical Documents. Our team comprises two researchers from I2R (Dr Lu Shijian and Dr Su Bolan) and my PhD student (Ms Zhang Xi) and me. In the competition, we won first prize on one field (relation) and second prize on three other fields (age, birth place, marital status) among all the six fields for recognition.
  • Document Image Binarization Contest (DIBCO 2013): This contest was held in conjunction with the 12th International Conference on Document Analysis and Recognition (ICDAR 2013) in 25-28 August 2013, Washington D.C., USA. Dr. B Su and S Lu from I2R and Prof. C L Tan won the first prize in the contest. In total, 18 international teams participated in the contest.
  • Robust Reading Competition 2013 was also held in conjunction with ICDAR 2013. The competition consisted of several subtasks involving text localization, segmentation and recognition in document images and scene images. Dr S Lu from I2R and Prof C L Tan with his student Mr S Tian won the subtask on Text Segmentation in Real Scene images. Our solution was the best among 5 participating teams.
  • Outstanding Service Award, 2011: This award was presented to me as a Program Chair at the 11th International Conference on Document Analysis and Recognition, Beijing, China, 18-21 Sept 2011.
  • Handwritten Document Image Binarization Contest (H-DIBCO 2010): This contest was held in conjunction with the 12th International Conference on Frontiers in Handwriting Recognition, in 16-18 November 2010, in Kolkata, India. Dr. S Lu from I2R and Prof. C L Tan and his student Mr. Su Bolan won one of the two first prizes in the contest. In total, 16 international teams participated in the contest.
  • Document Image Binarization Contest (DIBCO 2009): This contest was held in conjunction with the 10th International Conference on Document Analysis and Recognition (ICDAR 2009) 26-29 July 2009, in Barcelona, Spain. Dr. S Lu from I2R and Prof. C L Tan beat 35 other international competitors to clinch the first place in the contest.
  • BioCreative II Challenge Workshop, 2007: Jointly with Dr. J Su at I2R, we participated in the BioCreative II evaluation ( by submitting our Text Categorization technique based on Relevance Frequency measure in the Sub-Task for detection of Protein-Protein Interaction Articles in MEDLINE abstracts. In terms of F1 score, our submission was ranked the top among 51 submissions from 19 international teams. We achieve the best performance in F1 score of 0.78. The top three teams include also Tsinghua University and Edinburgh University. Other teams include UC Berkeley, University of Colorado, founder of Bioinformatics, etc.
  • HP Digital Publishing for Teaching and Learning Grant: NUS is one of the 14 colleges/universities worldwide that was awarded this grant in 2006 by HP in recognition of my research in document image processing. The grant (amount US$58,000) was given to support research project in "Document Information Mining for Digital Libraries"
  • Best Student Paper Award: awarded during the 7th International Workshop on Document Analysis Systems, Nelson, New Zealand, 13-15 Feb 2006, for our paper "Semi-automatic Ground Truth Generation for Chart Image Recognition" by L Yang, W Huang and C L Tan.
  • Best Poster Paper Award: awarded during the 8th International Conference on Document Analysis and Recognition, Seoul, Korea, 29 Aug - 1 Sept 2005, for our paper "Warped Image Restoration with Applications to Digital Libraries" by L Zhang and C L Tan.
  • BioCreative (Critical Assessment of Information Extraction systems in Biology) Workshop, 2004: Jointly with Dr. J Su's team at I2R, we won the competition among 15 international teams (including Stanford U, Edinburgh U, UPenn and European Bioinformatics Centre) for the task (closed division) of recognizing protein/gene names from biological technical papers at 82.6 F score.
  • AAAI Deployed Application Award: awarded during the 16th Annual Conference on Innovative Applications of Artificial Intelligence (IAAI2004), San Jose, California, 27-29 July, 2004, for our paper "Making Better Recommendation for Online Profiling Agents" by D Oh and C L Tan presented at IAAI-04. This is an annual award given by Association for the Advancement of Artificial Intelligence (AAAI) for selected successful innovative applications of AI during their annual AAAI conference. In 2004, four teams received this award, and of these four teams, NUS was the only team outside America, the other 3 teams being from USA.

Supervision of Graduate Students

  • Total No. of PhD students supervised and graduated: 30
  • Total No. of PhD students currently supervised: 5
  • Total No. of MSc students supervised and graduated: 37

Professional Services

  • Program Co-chair, 14th International Conference on Frontiers in Handwriting Recognition, 2014 (ICHFR2014), Crete, Greece
  • Program Co-Chair, International Conference on Document Analysis and Recognition (ICDAR) 2011, Beijing, China
  • Chair, PAKDD School, 10th Pacific Asia Conference on Knowledge Discovery and Data Mining (PAKDD2006), Singapore
  • Co-Chair, PAKDD 2006 Data Mining Competition, Singapore
  • Area Chair IEEE International Workshop on Applications of Computer Vision, 2005 (WACV 2005), Breckenridge, Colorado, USA
  • Member of program committees of over 40 international conferences

Invited Talks

  • "Robust Reading from Images and Videos", Keynote Talk, International Conference on Signal and Image Processing, ICSIP 2014, Bangalore, India, 8-10 January 2014.
  • "Document Image Enhancement", Invited Talk, Institute of Automation, Chinese Academy of Science, Beijing, 25 May 2011.
  • ""Document Image Retrieval", Technologies for Next Generation Media Search, organized by Industry Liaison Office, NUS, 12 Aug 2010, I3 Building, Singapore
  • "Pattern Recognition and Medical Imaging", Computer-Aided Diagnosis, Treatment and Prediction Workshop, jointly organized by Singapore Bioimaging Consortium and Institute for Infocomm Research, 15 Jan 2009, Biopolis, Singapore
  • "Pattern Recognition in Biomedical Imaging", Ocular Imaging Symposium 2008, 26 June 2008, Singapore National Eye Centre, Singapore
  • "Automated Retrieval and Generation of Brain CT Radiology Reports", 7th Korea-Singapore Joint Workshop on Bioinformatics and Natural Language processing, 15-16 Feb 2008, Seoul, Korea
  • "Document Image Analysis - Introduction & Advanced Topics", Centre for Strategic Infocomm Technologies, CSIT, 1-2 Oct 2007, Singapore
  • "Restoration of Warped Document Images", Seminar Series on Communications, Networking, Signal & Image Processing, Dept of Electrical and Computer Engineering, Purdue University, 4 Sept 2007, West Lafayette, USA.
  • "A wording image coding technique and its applications in information retrieval from imaged documents", International Workshop on Document Analysis, 8-11 March 2005, organized by the Indian Statistical Institute (ISI), Kolkata, India. ISI is the top Research Institute in India.
  • "Document Image Restoration" at the Records Management Workshop, 19 March 2001, organized by National Archives of Singapore, National Heritage Board.
  • "Document Image Analysis Research at the National University of Singapore", 28 May 1999, Samchok National University, Korea.
  • "Text Extraction from Document Images" AI Seminar Series, 21 May 1999, Kyushu Institute of Technology, Iizuka, Kyushu, Japan.
  • "Kanji as Lexical Constraints in Alignment of Japanese and Chinese Texts" at Natural Language Processing Special Interest Group Seminar, 27-28 May 1994, Tokyo Institute of Technology, Tokyo, Japan.
  • "Artificial Intelligence in Medicine" 2nd SMA Computer Conference, 6 September 1987.
  • "Selecting the First Project" at AI Workshop on Expert Systems, 4-8 May 1987, Institute of Systems Science, Singapore