Welcome to Phan's homepage! I am a professor at the Department of Mathematics, The University of Tennessee-Knoxville. I did my graduate study in the University of Minnesota (Twin Cities-Minnesota-US) and obtained my Ph.D. degree in 2007. My research is in partial differential equations. I study existence, uniqueness, and regularity estimates of solutions. I also work on nonlinear dynamics of solutions, and optimal control problems in mathematical biology. The math formula above is an a-priori estimate of the unknown solution \(u\) of a class singular-degenerate coefficient PDEs. This formula appears in my recent work, which is a joint work with Hongjie Dong and published here by the AMS. Additional information about me can be found in this article (in Vietnamese) published by Vietnamnet, and also in an interview video (in Vietnamese) in the #toan0mau series produced by professor H. V. Tran.