Electronic Journal of Differential Equations,
Vol. 2009(2009), No. 109, pp. 1-16.

Title: A quasi-boundary value method for regularizing
       nonlinear ill-posed problems

Authors: Dang Duc Trong (Ho Chi Minh City National Univ., Vietnam)
         Pham Hoang Quan (Sai Gon Univ., Vietnam)
	 Nguyen Huy Tuan (Ton Duc Thang Univ., Vietnam)

Abstract:
 In this article, a modified quasi-boudary regularization method
 for solving nonlinear backward heat equation is given.
 Sharp error estimates for the approximate solutions,
 and numerical examples to illustrate the effectiveness
 our method are provided.  This work extends to the nonlinear
 case earlier results by the authors [33,34] and by
 Clark and Oppenheimer [6]. 

Submitted June 19, 2009. Published September 10, 2009.
Math Subject Classifications: 35K05, 35K99, 47J06, 47H10.
Key Words: Backward heat problem; nonlinearly Ill-posed problem,
           quasi-boundary value methods; quasi-reversibility methods,
           contraction principle.