Event(s) on October 2011

• 4/10/2011

  題目:	Phase-field models for multiphase complex fluids: modeling, numerical analysis and simulations
  講員:	Prof. SHEN Jie, Department of Mathematics, Purdue University, USA
  時間/地點:	16:30  -  17:30 FSC1217, Fong Shu Chuen Library, HSH Campus, Hong Kong Baptist University
  摘要:	I shall present some recent work on phase-field model for multiphase incompressible flows. We shall pay particular attention to situations with large density ratios as they lead to formidable challenges in both analysis and simulation.

  
  

• 19/10/2011

  題目:	Recent Trends in Processing Low Quality Images for Biometric Identification
  講員:	Professor Bob Plemmons, Reynolds Chair of Computer Science & Mathematics, Wake Forest University, USA
  時間/地點:	15:00  -  16:00 FSC1217, Fong Shu Chuen Library, HSH Campus, Hong Kong Baptist University
  摘要:	Biometric recognition is a technique for checking and verifying identities that employs digitally created maps of an individual's physical characteristics. Modalities include fingerprints, voice recordings, iris scans, ocular region or face images, etc., the most reliable of which is considered to be iris recognition. However, effective iris recognition generally requires a compliant subject and high quality images, which are not always available in security applications. In this talk we describe some recent mathematical algorithms for biometric identification based on imaging the ocular region of the face, including the eyes, from from several meters range. Topics considered include new approaches for iris segmentation and comparisons with 5 different iris segmentation algorithms on challenging ocular images. The goal is to convey some of the difficulties in localizing the iris structure in images of the eye characterized by variations in illumination, eye-lid and eye-lash occlusion, de-focus blur, motion blur and low resolution. The 5 algorithms considered in this regard are based on the (a) integro-differential operator; (b) Hough transform; (c) geodesic active contours; (d) active contours without edges; and (e) directional ray detection methods. Experiments on the very difficult Face and Ocular Challenge Series (FOCS) database highlight the pros and cons of the individual segmentation algorithms. We conclude with a look at incorporating non-iris information in the general ocular region as well as some future directions in biometrics. This work is part of a team effort involving researchers at Carnegie Mellon, West Virginia, and Wake Forest.