[3] [3] ROSIN P L.A note on the least squares fitting of ellipses[J].Pattern Recognition Letters,1993,14:799-808.

[4] [4] GANDER W,GOLUB G H,STREBEL R.Least-square fitting of circles and ellipses[J].BIT,1994,34:558-578.

[5] [5] TAUBIN G.Estimation of planar curves,surfaces and non-planar space curves defined by implicit equations,with applications to edge and range image segmentation[J].IEEE Trans.Pattern Analysis and Machine Intelligence,1991,13(11):1 115-1 138.

[6] [6] BOOKSTEIN F L.Fitting conic sections to scattered data[M].Computer Graphics and Image Processing,1979,9(1):56-71.

[7] [7] TAKEUCHI K,COLLIER N.Bio-medical entity extraction using support vector machines[C].Proc ACL 2003Workshop on NLP in Biomedicine,Sapporo,2003.

[8] [8] JOACHIMS T.Learning to classify text using support vector machines:[Dissertation][C].Norwell,MA,USA:Kluwer Academic Publishers,2002.

[9] [9] ORAZIO T D,LEO M,CICIRELLI G,et al.An algorithm for real time eye detection in face images[C].Proceedings of the 17th International Conference on Pattern Recognition,Cambridge,2004.